I agree. The power differential is implied by the situation itself. It has nothing to do with client wanting or not wanting to give it away. When you come to someone for help and spill your guts to them, but they don't have to reveal anything about themselves and their role is to be of help to you and not make it a two-way give-and-take relationship, a certain degree of dependency and vulnerability develops naturally whether you want it or not. If client feels completely equal to therapist, no dependency at all, it simply means they are not talking about a lot of deeply personal things in therapy in order not to reveal their vulnerabilities. But if you don't talk about some intimate personal issues with the therapist, than what's the point of therapy then? Then it's a waste of time and money because it defeats the purpose.